Conversion of digital power must be working in the turn-on and turn-off status. Each operation of turn-on and turn-off is completed in a limited period of time and the duration for the turn-on and turn-off status of the switching components (or circuits) is determined by their properties. Each turn-on or turn-off operation will cause consumption. The value of the switching consumption equals to the value obtained by integrating multiplication of the current flowing in the switching components (or circuits) by the voltage across the switching components (or the circuits) over the duration of one turn-on or turn-off operation. Thus, the higher the switching frequency of the switching component is, the more the switching consumption becomes. Especially when the frequency is very high, such switching consumption becomes majority of the consumption and can increase the aggregate switching consumption of the switching components. Sometimes, such switching consumption can even take more than 15% of the total power. And such switching consumption will cause negative influences to the switching components (or circuits), for instance, the increase of the working temperature, the excursion of working parameters of the switching components (or circuits), etc. In order to diminish this kind of switching consumption, many technologies relating to soft-switching are being developed. The working principle of these technologies is to make the current flowing through or the voltage across the switching components (or circuits) be zero or near zero during the turn-on and turn-off operation. In this way, the switching consumption shall be decreased accordingly. But heretofore, these types of soft-switching technology can only be used in DC power converts controlled by invariable frequency. And auxiliary circuits of such types of soft-switching are of great complexity with multiple components.